Abstract: Qigu Group inspissated pool, located in No. 9 Block, Xinjiang is buried in the depth of 180m. It’s decided to use slotted screen liner for horizontal well completion, thanks to the incompaction and loosely cement compacted formation. To select the width of slot, screen analysis for the core is performed. When the cumulative weight percent of big size sand is 10%, the corresponding sand size is 0.22-0.25mm. Based on the principle of 1/3-2/3 bridge, the width of slot will be 0.44-0.50mm. Actually the width of slot in all horizontal wells is modified to 0.45mm. There is no severe sanding problems during the period of pilot production. The designed width of slot may be further optimized after long-term pilot production.